Tapping-furnace.



G. 0. SEWARD.

TAPPING FURNACE. APPLICATION FILED MAY 3, 1904.

940,561. v Patented N0v.16,1909.

INVENTOR: WITNESSES: 4a 0- Jul/m! 0%! By A/Zomys, 1

GEORGE O. SEW'ARD, OF HOLQGT/IBS ROCK. VIRGLENIA, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO ELECTED METALLURGICAL COIVIEANZ, A CORPORATION OF WEST VIRGINIA.

TAPPING-FUBNACE.

Specification of Letters Patent.

Application filed May 3, 1904. Serial No. 206,252. I

T 0 all whom it may concern:

lie it hnoivn that l, (linonon O. Smvnnn, a citizen of the United States, residing at llolcombs Rock, in the county of lledtord and State of Virginia, have invented certain new and useful Improvements in, lapping-l un naees, of which the following is a specification.

ln tapping furnaces, 'and especially electric Furnaces in which highly refractory ma terials are encountered, the tap hole often bra-nines tilled with slag and metal despite the greatest care used in applying the clay or other filling for closing it after tapping. ln such cases it is very ditlicult to drive the tapping bar through the obstructions when it is desired to tapthe iurnace again. lt oc- (nsionally happens that the bottom of the molten metal in the furnacebecomes chilled. rendering the opening oi the furnace almost. impossible. and always necessitating a great amount of sledging and drilling with steel barsi' The present invention aims to obviate these ditliculties, and provides for electrically generating heat to burn a hole through the material filling the tap hole of the furnace, preferably by the application of an electric arc.

The invention provides also for the introduction of a special plug in the tap hole, which may 'be pulled out. of or driven through the same, or which may be melted out according to the necessities of the case.

Suppose for example an ordinary electric furnace is used. After the tap hole has been plugged up with clay or the like, an iron rod smaller than the tap hole (say an inch or an inch and a half in diameter) is driven through the clay t'ar enough'to make electrical connection with the conductive con tents of the furnace. Then in order to tap the furnace at special tapping electrode is l)i' ()li,,lll) up to the iron rod to establish an are between the two. This are is maintained, melting away the incoinlnistible iron rod and clay, and the tapping electrode is gradually advanced into the furnace until the hole made reaches the contents of the furnace. I

A suitable apparatus is illustrated in the accompanying drawings.

l igurc l is partly a section and partly an elevation of an electric furnace at. the beginning oi? the process described; 2 is a lrag 'nentary View at an advanced stage of the process.

Referring to the specific apparatus illustrated, It is an electric furnace of the u'stial or any suitable type having two electrodes ll and C by which theniizgture in the furnace is melted in the usual manner. From one of the. electrodes (or from any other suitable point of connection) a hraneh'cable D 6X- tends to the vicinity of the tap hole, where it is mechanically and electrically connected through a metal socket D with a tapping electrode E of carbon, a handle F of noneonducting material being also attached to the socket I).

With this apparatus, after each tapping, the tap hole ti is plugged with clay or other suitable ineombustible material l-l. Then .a rod J of iron or other incombust'ible conducting material is driven into the tap hole until its inner end makes connection with the contents of the furnace. Now when it 'is desired to tap, it may be found that the rod J can be withdrawn or driven in Without great diliieulty, opening the tap hole at once without the necessity of using the electrode ll. lint supposing the slag or metal at the inner end of the rod J to have become hardened or crusted around the tap hole to such extent as to prevent removal of the rod J, then the electrode E 153 brought up to the rod J, and an are established between the two. i

This are melts away the rod J and the surrounding clay ll, and may be gradually advanced by advancing the electrode E (Fig: 2) to such point as to release the contents or to permit the driving; in of the rod J.

The process is not restricted to the specitic apparatus shown. nor to any particular style of furnace. It. has been used with success in electric furnaces of the single pole type in which the crucible itself forms one electrode. It is only necessary in such cases to use care to avoid overloading the tapping electrode by a current directly from the crucible.

It is to he observed that the Word removable is applied to the bar J in a broad sense, which includes pulling it out and driv-' ing it in, and also melting it away.

Though I have described with great particularity ct detail a certain process and apparatus embodying this invention, yet it is not to be understood therefrom that the invention is limited to the specific embodiments described.

Various modifications in detail and in the arrangement lllLtCOXIlblIlEltlOIl of the parts of the apparatus may be made by those skilled in the art without departure from the invention.

Vthat I claim is 1. The process of operating a tapping furnace, which consists in closing the tap hole with a plug of incombustible material which includes a conductor, providing an electric are at the tap hole, and melting out the closing material therewith.

2. The process of operating an electric tappin furnace which consists in closing the tap ho e by means including a conductive material, and opening 'the tap hole by the heat from an electric current arcing to and carried through t me conductive material.

3. The process of operating an electric tapping furnace which consists in closing the tap hole with a refractory material, and driving a rod of conductive material there through into contact. with the conductive contents, and. opening the tap hole by establishing an are between said rod and an external electrode and thus burning a hole into the furnace.

t. The process of o ierating a tapping furnace which consists in closing the tap hole with a refractory material, driving therethrough a removable rod, and removing said red by melting away the same.

5. The combination with an electric furnace. oi an external electrode and a conduct-- ivc rod connecting with the conductive contents and passing to the outside of the furnace, said electrode being arranged in position to spring an electric arc to said rod.

(S. The process of operating a tapping furnace, which consists in closing the tap hole by a plug primarily coneisting of incombustiblc electrically-non-conductive material, and opening: the tap hole by melting out. the plug by means of an electric arc.

in witness whereof, I have hereunto signed my name in the presence of two subscribing 'ltlltr'SGS.

GEORGE O. SEWARD.

Witnesses 7 (inc. T. IJANCASTER, E, vox Kii'GnmnN. 

